Coal cleaning apparatus



Sept. 7, 1965 K. PRINS COAL CLEANING APPARATUS 5 Sheets-Sheet 1 Filed Dec. 17, 1962 6F g NW N mm f a w 5 \.0 QM. R V mm .Q J w .wm mm .3 mm y Mk mm vw \w R R mm vm w km .w\ mw :5: a a w m I: l: mm I mm E .3 :1 L Q mm Q (w vm mm M Q mv INVENTOR... KLAAS PR/N-S' BY MAHO/VE'Y MILLER 8 RAMB Sept. 7, 1965 K. PRINS COAL CLEANING APPARATUS Filed Dec. 17, 1962 FIG 5 Sheets$heet 2 INVENTOR... K LAA 5 PHI/VS ATTORNEYS Sept. 7, 1965 K. PRINS COAL CLEANING APPARATUS 5 Sheets-Sheet 3 Filed Dec. 17, 1962 INVENTOIL. KLAAS PR/NS FIG: 5

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COAL CLEANING APPARATUS Filed Dec. 17, 1962 5 Sheets-Sheet 4 2a 0 66' [H I' I 67 v O I: I 1'? m" L 7 Q I i i I! 1 I! I] Q 0 I;

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COAL CLEANING APPARATUS Filed Dec. 17, 1962 5 Sheets-Sheet 5 INVENTOR. KLAAS PHI/VS BY MAHO/VEY, MILLER 8 RAMBO A TTORNE Y8 United States Patent 3,204,764 COAL CLEANING APPARATUS Klaus Prins, 104 E. D. St, Wellston, Ohio Filed Dec. 17, 1962, Ser. No. 245,177 Claims. ((11. 20918) My invention relates to Coal Cleaning Apparatus. It relates, more particularly, to coal cleaning apparatus or washers of the general type disclosed in my prior patents, Nos. 2,082,467, issued June 1, 1937 and 2,246,532, issued June 24, 1941.

Separation of impurities from coal is known by the trade as coal cleaning. Coal cleaning is upgrading of the coal output of the mine resulting in a more readily salable product with higher heat value or more B.t.u.

All coal cleaning devices are dependent in their operation on the difference in specific gravity of the coal particles and that of the impurities. It is generally understood that a bituminous coal of 1.35 specific gravity has the highest Btu. content available and any materials of a higher specific gravity mixed in with this product will have a much lower heat value and a large quantity of such impurities can make the product unsuitable. Usually the most objectionable impurities occur in the form of slate, pyrites, bone coal, fire clay and rock.

In the simple coal washing processes, a separation of the impurities from coal can be accomplished at a specific gravity of about 1.55. Everything less than 1.55 can be included in the cleaned coal product and everything heavier than 1.55 specific gravity is considered reject material.

The general type of washer disclosed in said patents and in this present application can be classified as a flow washer. This type of washer depend-s entirely on the velocity of the controlled currents occurring in the washer. In this type of washer, the material to be processed is all submerged in the water which is a desirable condition because a coal particle of a 1.35 specific gravity has a relative weight of .35. The impurities on the same basis can be considered as having a weight of .55. The differential created by submerging is equal to or about 60%. If a piece of coal and a piece of refuse under the above condition are subjected to a current of water, the coal particle will be carried or moved in the direction of the water current while the refuse particle will remain in its same position.

The washer of my prior patents and that disclosed herein consists of a stationary tank or washer tank and a washer shaker. An inlet for the raw coal is provided at the upper end of the tank and leads into the shaker. An inlet pipe nozzle for providing a stream of water under suitable velocity is provided at the one end of the tank and leads into the washer shaker at a low level. Adjacent the inlet end of this pipe is a water inlet neck with a throat over which the raw coal is fed and where it is subjected to the current of water from the inlet pipe nozzle. An outlet for the clean coal is provided at the other end of the washer shaker and tank at a higher level. In the bottom of the tank below the inlet pipe nozzle and associated throat is an outlet for the water, The washer shaker is suspended on toggles 0r hanger arms for swinging movement relative to the tank and the shaking movement is caused by the rotation of a connected drive shaft or crankshaft which provides an oscillating motion to the shaker. The hanger arms are initially positioned at an angle from the vertical and the bottom of the washer shaker is inclined toward the throat associated with the inlet nozzle end of the water pipe. A refuse outlet is provided in the bottom of the tank and communicates with the throat of the washer shaker. This positioning of the hanger arms and the inclination of the bottom of the shaker will cause a movement of the refuse material through the throat toward the refuse outlet when the shaker is actuated. If no water is flowing through the apparatus, all material would travel toward the refuse outlet. Introducing a current of water adjacent the shaker through the throat, which communicates with the refuse outlet and is directed toward the clean coal outlet of the shaker, will carry the coal particles in the current toward such clean coal outlet.

According to my present invention, the washer shaker fits closely inside the washer tank with only a nominal working clearance. A flexible seal is provided between the shaker and the tank so as to provide two compartments in the lower portion of the washer tank, one of which is provided with the water outlet previously referred to and the other of which is provided with the refuse outlet. From the first compartment, which is at the end of the tank where the shaker clean coal outlet is located, water can reach the outlet provided therefor only through a screen provided in the bottom of the washer shaker. The purpose of this arrangement is to reduce the velocity of the water at the clean coal discharge end of the washer and have a current sufficiently strong to carry coal particles and not strong enough to carry refuse particles. The second compartment is adjacent the water inlet nozzle and throat and the refuse outlet leads from the bottom thereof. This makes it possible to provide a strong current of water at the throat of the washer shaker allowing only refuse particles to move toward the refuse outlet and forcing the coal particles in this stronger current toward the clean coal discharge outlet.

With this arrangement, a number of refuse particles will be carried along with the coal toward the clean coal outlet. However, the water draw-off from the bottom of the first compartment, as previously explained, will reduce the flow velocity and the refuse particles, being heavier than the coal, will drop out of the current and will form a bed below the top current. This bed will also contain coal particles sometimes caught below a refuse particle on its way to the refuse bed.

Due to the oscillating motion of the shaker, this bed is more or less in constant suspension and forms a fluid mass. In such an intermingling of particles, the heavier materials will continuously find a lower level forcing or displacing the lighter particles toward the upper levels where they are subjected to the upper flowing current and are carried along in the clean coal stream toward the clean coal outlet.

Another improvement of this present invention consists of a different type overflow weir located at the clean coal outlet. In flow washers of this type it has always been a problem to eliminate or separate the light fiat pieces of slate from the coal. This type of material has a tendency of riding along in the current and will only disappear when they turn at With a thin edge downward. The improved weir embodies a toothshaped weir'which has been found to bring about very satisfactory results. The weir oscillating with the shaker presents a barrier against the onflowing current of coal and water. The larger pieces of coal appear at times above the water current at the point of discharge over the weir and the thin pieces of slate are turned over at this point and become intermingled with the refuse bed and are further disposed of with the refuse.

According to this invention, I also provide an adjustable gate plate which, in combination with the inclined bottom of the washer shaker, forms the throat adjacent the Water inlet nozzle. This gate plate is perforated to allow the water to flow through the perforations. Since water will flow along a path of least resistance, when the quantity of refuse accumulates in front and below this adjustable plate, the water will flow upwards through the perforations, thereby reducing the velocity through the throat opening between the top of the refuse accumulation and the edge of the plate, and allow for a more rapid discharge of the refuse.

According to this invention, I have also provided an improved feeding device for the raw coal to allow the materials to flow into the washer at a constant rate.

In the accompanying drawings, the preferred embodiment of this invention is illustrated and in these drawings:

FIGURE 1 is a vertical sectional view taken along line 11 of FIGURE 2 through a coal cleaning apparatus or machine in which my invention is embodied.

FIGURE 2 is a plan view of the apparatus of FIG- URE 1.

FIGURE 3 is a perspective view of sections of the perforated or foraminous bottom of the washer shaker.

FIGURE 4 is a perspective view of the coal-cleaning apparatus with side panels removed for clarity.

FIGURE 5 is an enlarged detail in vertical section illustrating the oscillating mechanism for the washer shaker.

FIGURE 6 is a detail in plan of the mechanism shown in FIGURE 5.

FIGURE 7 is a transverse sectional view taken along line 7-7 of FIGURE 6.

FIGURE 8 is a detail in perspective illustrating the perforated adjustable gate plate which aids in forming the inlet throat of the washer shaker.

FIGURE 9 is a schematic view illustrating the flow of material and water in the apparatus during the separating operation.

With reference to the drawings and particularly to FIGURES 1, 2, and 4, my present invention is shown as embodied in coal cleaning apparatus which consists mainly of a stationary washer tank 11 and a relatively movable washer shaker 12. The tank 11 is suitably fabricated in a watertight manner preferably from metal frame members and plates and is preferably in the form of an upright tank of rectangular cross section.

The tank 11 is open at its upper side and intermediate its ends there is provided an inlet feed chute 13 of rectangular form which leads from a suitable source of raw coal to be cleaned. At the lower end of this chute which projects downwardly into the tank 11, there is an adjustable gate (FIGURE 1) 14 mounted on the lefthand wall thereof by means of pins and slots 15 for vertical adjustment. At the outlet or right-hand end of the tank adjacent its upper end is an outlet spout or discharge sluice 16 for clean coal which will lead it to a suitable location. At the inlet or opposite end of the tank 11 a water inlet pipe 17 is provided leading into the tank at a low level and having an inlet nozzle 18 of rectangular form projecting into the tank which is angled at its inner end, as indicated at 19, to direct the water downwardly toward a refuse outlet 20 of rectangular outline through which water and refuse carried therewith is discharged. The outlet 20 will communicate with a watertight refuse conveyor (not shown) which will have a water level corresponding to that of the washer. Thus, the water in the washer adjacent the outlet has no current through the outlet 20, the refuse merely dropping through the body of water into the refuse conveyor. Flow of water into the pipe 17 is controlled by a suitable manually operable flow control valve 21. To the right of the outlet 20 or beyond it in the direction of flow of the water from the pipe 17 is a water outlet 22 of rectangular form in the bottom of the tank 11 which is controlled by a suitable control valve (not shown). A fixed angularly disposed wall 23 is provided in the lower righthand corner of the tank 11 and extends from the water outlet 22 to the clean coal outlet 16. Also, the opposite lower corner of the tank 11 is provided with an angled corner wall 24 through which the water pipe 17 extends.

The washer shaker unit 12 is suspended for oscillation 4 in the tank 11 and fits closely within the washer tank with only a nominal working clearance, as indicated best in FIGURE 2. It is in direct communication with the tank and as a result, the level of the water in both will be the same. The shaker unit 12 is formed of two upright side panels or plates 25 which lie closely adjacent the sides of the tank and each of which has a straight upper edge 26 and an angled lower edge 27. The plates 25 are connected together at one end by a cross plate 28 at the inlet side of the tank which is provided with an enlarged opening 29 through which the inlet nozzle 18 of the pipe extends and by a cross brace which may be in the form of a channel member 30 disposed below the opening 29. At their opposite ends, the plates 25 are connected together by a cross brace 31 which may be in the form of an angle member.

The unit 12 is suspended within the unit 11 by means of hanger arms 35 located at the four corners of the tank. These arms 35 are pivoted at their lower ends by pins 36 to the respective plates 25 adjacent their ends. The arms 35 are suspended at their upper ends from transversely disposed shafts 37 which extend across the upper open end of the tank 11. These shafts 37, as shown best in FIGURE 2, are mounted in bearings 38 provided on the upper edges of the opposite side walls of the tank 11. For oscillating the washer shaker within the tank, the mechanism illustrated best in FIGURES 1, 2, 4, and 5 is provided. This mechanism comprises a connecting rod 40 which is connected at one end by a suitable yoke and clamping arrangement 41 to a pivot pin 34 which is carried by an extension 33 of the unit 12 which is carried by the cross plate 28. The opposite end of the connecting rod is connected to an eccentric arrangement by means of a suitable yoke and clamping unit 42. This eccentric arrangement comprises the eccentric 43 which is carried by a transverse shaft 44 that is rotatably mounted in bearings 45 secured to the fixed support frame 39, that is located at this end of the tank. The shaft 44 has keyed on one end thereof a flywheel 46. This flywheel 46 is driven by a suitable belt drive 47 which is enclosed within a guard 48. This belt drive is preferably driven by an electric motor 49. The motor 49 and the guard 48 are carried by the fixed frame 39. Thus, operation of the motor 49 will produce oscillation of the shaker 12 within the tank 11. The connecting rod 40 is of such length that it initially pulls and holds the hanger arms rearwardly away from vertical position and prevents them from reaching vertical position during oscillation. This tends to throw the material in the shaker upwardly to keep it in suspension during oscillation of the shaker so as to crowd the lighter material upwardly and the heavier downwardly.

The shaker 12 is provided with an inclined bottom 50 (FIGURES 1 and 4) along the lower inclined edges 27 of the plates 25. This inclined bottom along with the angled hanger arms 35 tends to move the refuse material toward the outlet 20 when the shaker unit 12 is oscillated, it being noted that the lower edge 51 of the bottom terminates just above the outlet 20 at its transverse center line. The bottom 50 includes trays or sections 52 which are shown removed in FIGURE 3 and in position in FIG- URE 1. These sections or trays are constructed to permit the passage of water through the bottom being of perforated or foramin-ous construction. These trays are removably mounted in suitable openings in the bottom 50 and the bottom is imperforate downwardly of the lower end of the lowermost tray.

At the lower end of the lowermost tray 52, I provide, according to this invention, a flexible baffle member or wall 55. This baffle may be of rubber or other suitable flexible material and extends completely across beneath the bottom 51 between the side walls 25 of the tank and is located between the shaker bottom 50 and a humped bottom portion 56 of the bottom of the tank. This baffle 55 being flexible permits oscillating movement of the unit 12 in the tank. However, its main purpose is to divide the lower portion of the tank into a first compartment 61 communicating with the clean coal outlet 16 and the water outlet 22, and a second compartment 62 communicating with the refuse outlet 20 and the inlet pipe nozzle 18, these compartments being relatively independent. The throat 65 also connects these two compartments. It will be noted that the innermost upper edge 63 of the water inlet nozzle 18 is substantially in vertical alignment with the lowermost edge 51 of the shaker bottom 50. Cooperating with the water inlet nozzle 18 and with the bottom wall 50 of the shaker 12 is an adjustable foraminous or perforated gate 64 which is shown in place in FIGURE 1 and the details of which are shown in FIGURE 8. This gate 64 is disposed above the inlet end of the nozzle 18 and extends toward the bottom 50 of the shaker but its lower edge is spaced therefrom to provide a material-separation throat 65. The gate 64 is pivoted at 66 to the vertical transverse wall 28 for vertical swinging adjustment. It is adjusted about this pivot 66 by means of a link 67 which has its lower end pivoted to the lower end of the gate as at 68. The upper end of the link 67 is adjustably secured to a bracket 69 by means of a clamping bolt and slot connection 70. Thus, the vertical extent of the throat 65 may be adjusted by adjustment of the gate 64 relative to the bottom 50. The gate 64 and lower imperforate part of the bottom 50 thus provide a neck into which the current of water enters from the nozzle 18 and into which material to be separated will tend to enter through the throat 65.

Over the gate 64 is a material-directing batfie 71 which is inclined toward the vertical wall 28 but is spaced therefrom so that its lower edge is above the gate 64. This battle is secured to the shaker side walls 25 and is spaced below the angled lower edge of the chute 13 in parallel relationship thereto. The adjustable chute gate 14 can be adjusted relative to the inclined baffle 71 to vary the amount of material feeding toward and dropping from the baflle 71 onto the gate 64.

Adjacent the clean coal outlet 16 I provide a novel type of overflow weir which is indicated by the numeral 75. This weir is shown best in FIGURES 1, 2, and 4 and is supported by means of a transversely extending angle member 76 which is attched to the shaker side plates 25. This weir is of serrated or tooth-shaped form with the teeth extending upwardly and outwardly at an angle toward the outlet 16. The upper end of the bottom 50 is imperforate and extends upwardly and outwardly at the same angle as the weir, as indicated at '74. The angle 76 carries a flexible lip or strip 77 which wipes on the angle 31 to prevent excessive leakage from the compartment or chamber 62 and which still permits the necessary oscillating movement of the shaker unit 12.

The operation of this coal cleaning apparatus will be best understood by referring to the flow diagram in FIG- URE 9. The raw coal enters the apparatus through the inlet chute 13 and the amount dropping onto the gate 64 can be adjusted by the setting of the gate 15. Water under suitable velocity will enter the tank through the inlet pipe 17 and it will be understood that the tank 11 will be substantially filled with water. The velocity of the water entering the tank is adjusted as necessary by the setting of the valve 21. The gate 64 will be selectively set relative to the shaker bottom 51 to adjust the vertical extent of the throat 65 as required for various raw materials. The valves for controlling the flow from the outlets 20 and 22 will be adjusted as necessary.

The raw coal to be cleaned will reach the throat 65 and there will be subjected to the current of water from the inlet nozzle 18. This will carry the clean coal particles in the current of water upwardly through the throat 65 and along the shaker bottom 50 toward the clean coal outlet 16 and over the weir 75. Due to the oscillation of the shaker unit 12, the refuse material will tend to move along the bottom 51 back downwardly through the throat 65 and off the lower edge 51 of the bottom and drop through the outlet 20. Water from the inlet nozzle 18 can reach the water outlet 22 of the first compartment 61 at the bottom of the tank 11 through the perforations in the sections 52 of the shaker bottom 50. Consequently, the velocity of the water at the clean coal outlet 16 is reduced so that there is a current there sufficiently strong to carry the coal particles but not strong enough to carry most refuse particles. The other compartment 62 makes it possible to have a sufficiently strong current of water at the throat 65 which allows only refuse particles to move rearwardly and downwardly through the strong current toward the refuse outlet 20. With this separate compartment arrangement, a number of refuse particles may be carried along with the coal particles toward the clean coal outlet 16. However, the water draw-off from the first compartment 61 will reduce the flow velocity and the refuse particles, being heavier than the coal particles, will drop out of the current and will form a bed below the top current that will be along the shaker bottom 50. This bed may also contain coal particles which are caught below refuse particles on their way to the refuse bed. However, due to the oscillation of the shaker bottom 50, the bed is more or less in constant suspension and forms a fluid mass. In such an intermingling of particles, the heavier materials of the bed will continuously find a lower level forcing or displacing the lighter particles toward the upper levels of the bed where they are subjected to the upper current flowing toward the outlet 16 and are carried along in the clean coal stream to that outlet. The refuse on the shaker bottom 50, due to the shaker motion will gradually work back through the throat 65 and drop into the refuse outlet 20. The material in the current of water will reach the serrated weir which will present a barrier to the onflowing current of coal and water. The larger pieces of coal will gradually work above the weir and flow on through the outlet 16 whereas the thin pieces of slate will be turned over at the weir and become intermingled with the refuse bed which is moving down along the shaker bottom 50. The gate 64 not only provides for adjustment of the depth of the throat 65 but since it is perforated, it allows flow of water upwardly through it as the resistance to flow of water upwardly through the throat is increased by accumulation of refuse in the throat. This, in turn, will reduce the velocity of the water upwardly through the throat and allow for a more rapid discharge of the refuse downwardly through the throat. The adjustment of the supply chute gate 14 may be such as to provide for a constant flow of raw coal into the tank.

It will be apparent from the above that I have provided coal cleaning apparatus which has all of the advantageous features of the apparatus disclosed in my prior patents together with many additional important advantages brought about by the improvements of the apparatus disclosed herein.

Although I refer to the cleaning of coal, it will be understood that this apparatus is also useful in the separation of other materials having a mixture of particles of diiferent specific gravity.

Having thus described my invention, what I claim is:

1. Coal cleaning apparatus comprising an upright washer tank and a washer shaker movably mounted therein, means for moving said shaker, said shaker having a bottom wall inclined toward one end of the tank, said shaker having a second wall inclined in a direction opposite to that of the bottom wall to form therewith a converging neck with a throat opening, means for feeding raw coal to be separated onto said second wall so that it will pass downwardly into association with said throat, means for directing a current of water into said neck through said throat and toward said inclined bottom wall, a clean coal outlet passage for discharge of clean coal moved upwardly along said bottom wall by said current of water with said outlet passage located at a level higher than the throat, a vertical imperforate bafile member below the bottom wall dividing the lower portion of the tank into first and second compartments which are relatively independent and respectively communicate with said throat and are located respectively substantially forwardly and rearwardly of said throat relative to the direction of said current of water, said bottom wall having water inlet means comprising a fora minous area above the first compartment to permit some of the water to pass downwardly therethrough into said first compartment and said bottom wall extending downwardly into cooperation with said second compartment to direct refuse thereinto, and means for withdrawing Water from the first compartment and refuse from the second compartment.

2. Coal cleaning apparatus according to claim 1 i which the said clean coal outlet passage extends transversely of said bottom wall and has a serrated weir extending thereacross and over which the clean coal moved upwardly along said bottom wall will pass.

3. Coal cleaning apparatus according to claim 2 in which the second shaker wall is foraminous to permit vertical passage of Water therethrough.

4. Coal cleaning apparatus according to claim 3 in which the second shaker wall is in the form of a gate which is vertically adjustable for setting in diiterent converging relationships relat-ive to said inclined bottom.

5. Coal cleaning apparatus according to claim 3 in which said means for feeding the raw coal comprises a third Wall on the shaker inclined in a direction opposite to the inclination of said second wall thereof, a materialsupplying chute directing raw coal onto said third Wall, and antadjustable gate cooperating with said chute for controlling the amount of raw coal flowing onto said third Wall.

References Cited by the Examiner UNITED STATES PATENTS 297,591 4/84 Frazier 209-457 1,622,580 3/21 Geddes 209157 2,082,467 6/37 Prins 209442 2,106,290 1/38 Akins 20918 2,164,796 7/39 Bird 209-422 2,246,532 6/41 Prin s 209-18 2,297,009 9/42 Mead 209-469 HARRY B. THORNTON, Primary Examiner. 

1. COAL CLEANING APPARATUS COMPRISING AN UPRIGHT WASHER TANK AND A WASHER SHAKER MOVABLY MOUNTED THEREIN, MEANS FOR MOVING SAID SHAKER, SAID SHAKER HAVING A BOTTOM WALL INCLINED TOWARD ONE END OF THE TANK, SAID SHAKER HAVING A SECOND WALL INCLINED IN A DIRECTION OPPOSITE TO THAT OF THE BOTTOM WALL TO FORM THEREWITH A CONVERGING NECK WITH A THROAT OPENING, MEANS FOR FEEDING RAW COAL TO BE SEPARATED ONTO SAID SECOND WALL SO THAT IT WILL PASS DOWNWARDLY INTO ASSOCIATION WITH SAID THROAT, MEANS FOR DIRECTING A CURRENT OF WATER INTO SAID NECK THROUGH SAID THROAT AND TOWARD SAID INCLINED BOTTOM WALL, A CLEAN COAL KOUTLET PASSAGE FOR DISCHARGE OF CLEAN COAL MOVED UPWARDLY ALONG SAID BOTTOM WALL BY SAID CURRENT OF WATER WITH SAID OUTLET PASSAGE LOCATED AT A LEVEL HIGHER THAN THE THROAT A VERTICAL IMPERFORATE BAFFLE MEMBER BELOW THE BOTTOM WALL DIVING THE LOWER PORTION OF THE TANK INTO FIRST AND SECOND COMPARTMENTS WHICH ARE RELATIVELY INDEPENDENT AND RESPECTIVELY COMMUNICATE WITH SAID THROAT AND ARE LOCATED RESPECTIVELY SUBSTANTIALLY FORWARDLY AND REARWARDLY OF SAID THROAT RELATIVE TO THE DIRECTION OF SAID CURRENT OF WATER, SAID BOTTOM WALL HAVING WATER INLET MEANS COMPRISING A FORAMINOUS AREA ABOVE THE FIRST COMPARTMENT TO PERMIT SOME OF THE WATER TO PASS DOWNWARDLY THERETHROUGH INTO SAID FIRST COMPARTMENT AND SAID BOTTOM WALL EXTENDING DOWNWARDLY INTO COOPERATION WITH SAID SECOND COMPARTMENT TO DIRECT REFUSE THEREINTO, AND MEANS FOR WITHDRAWING WATER FROM THE FIRST COMPARTMENT AND REFUSE FROM THE SECOND COMPARTMENT. 